AUTHOR=Liu Yuxiu , Huang Shuhua , Han Jing , Hou Chenchen , Zheng Dasheng , Zhang Zhengmao , Wu Jun 

TITLE=Development and Molecular Cytogenetic Identification of a New Wheat–Psathyrostachys huashanica Keng Translocation Line Resistant to Powdery Mildew

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.689502

DOI=10.3389/fpls.2021.689502

ISSN=1664-462X

ABSTRACT=<p><italic>Psathyrostachys huashanica</italic> Keng, a wild relative of common wheat with many desirable traits, is an invaluable source of genetic material for wheat improvement. Few wheat–<italic>P. huashanica</italic> translocation lines resistant to powdery mildew have been reported. In this study, a wheat–<italic>P. huashanica</italic> line, E24-3-1-6-2-1, was generated <italic>via</italic> distant hybridization, ethyl methanesulfonate (EMS) mutagenesis, and backcross breeding. A chromosome karyotype of 2<italic>n</italic> = 44 was observed at the mitotic stage in E24-3-1-6-2-1. Genomic <italic>in situ</italic> hybridization (GISH) analysis revealed four translocated chromosomes in E24-3-1-6-2-1, and <italic>P. huashanica</italic> chromosome-specific marker analysis showed that the alien chromosome fragment was from the <italic>P. huashanica</italic> 4Ns chromosome. Moreover, fluorescence <italic>in situ</italic> hybridization (FISH) analysis demonstrated that reciprocal translocation had occurred between the <italic>P. huashanica</italic> 4Ns chromosome and the wheat 3D chromosome; thus, E24-3-1-6-2-1 carried two translocations: T3DS·3DL-4NsL and T3DL-4NsS. Translocation also occurred between wheat chromosomes 2A and 4A. At the adult stage, E24-3-1-6-2-1 was highly resistant to powdery mildew, caused by prevalent pathotypes in China. Further, the spike length, numbers of fertile spikelets, kernels per spike, thousand-kernel weight, and grain yield of E24-3-1-6-2-1 were significantly higher than those of its wheat parent 7182 and addition line 24-6-3-1. Thus, this translocation line that is highly resistant to powdery mildew and has excellent agronomic traits can be used as a novel promising germplasm for breeding resistant and high-yielding cultivars.</p>